• The Journal of Society for e-Business Studies
• /
• v.15 no.3
• /
• pp.63-83
• /
• 2010

IPTV(Internet Protocol Television) is an innovation technology to lead the new media age. Internet protocol television (IPTV) is a next generation television converged with the Internet which are delivered portal services such as information search, games, movies, home shopping and banking. Generally, service quality affects to adopt or use these technologies. Quality of experience (QoE) is more issue to be considered than service quality because of the technological restriction and limitation that IPTV is accessed by the Internet. The QoE is defined as the cognitive and experienced quality measured with users through an experiment and is conceptually related to service quality. The objective of this paper is to suggest a methodology to measure the QoE of IPTV using a user testing. We find significant factors affecting QoE of IPTV through an exploratory study and measure QoE scores. We found the nine factors of graphics, picture, accuracy, access method, quality of contents, usability, security, and performance important for QoE. The QoE scores of picture, graphics, and quality of contents gained over the average score, but the overall score for IPTV service providers was not high and the QoE needs to be improved.

• Information and Communications Magazine
• /
• v.25 no.8
• /
• pp.12-19
• /
• 2008

네트워크 및 전송기술의 발달로 통신망을 이용하여 IPTV와 같은 서비스를 제공하는 것이 가능하게 되었다. IPTV는 기존 방송과 달리 IP 망을 통해 데이터의 송수신이 이루어지므로, 전송에러가 발생할 수 있으며, 이 경우 패킷의 손실 및 지연 등의 이유로 열화가 발생하게 된다. 이러한 열화는 사용자의 체감품질에 영향을 미쳐 IPTV서비스에 대한 사용자의 신뢰도를 저하 시킨다. 본 논문에서는 IPTV서비스에서 체감 품질 보장 및 품질 모니터링에 관한 IPTV국제 표준화 동향 및 규정을 소개하고, IPTV 사용자의 체감품질을 보장하기 위한 방법을 고찰한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2011.06a
• /
• pp.422-425
• /
• 2011

IPTV와 같은 멀티미디어 트래픽의 이용량이 증가함에 따라, 멀티미디어 서비스의 품질을 향상시키기 위한 스트리밍 전송 기법들이 연구되고 있다. 기존 연구들은 네트워크 상태를 고려한 스트리밍 전송으로 네트워크의 효율성과 공정성을 향상시켜 서비스 품질(QoS)을 보장하지만 사용자가 인지하는 체감 품질(QoE)을 동시에 보장하지 못하는 한계를 가지고 있다. 본 논문에서는 스트리밍 서비스의 체감 품질을 향상시키기 위해 비디오의 품질을 단계적으로 변화시키는 스트리밍 기법을 제안한다. 제안하는 기법은 수식 기반의 TCP(Transmission Control Protocol) 전송률을 기반으로 네트워크 상태를 측정하여 단계적으로 품질을 조절하고, 일정시간 동안 품질 조절의 수행을 제한한다. 이를 통해 급변하는 네트워크 상태 변화에 따른 잦은 품질 변화를 피하여 체감 품질을 향상시킨다. 실험을 통해 제안하는 기법의 유효성을 확인하였다.

• Journal of KIISE:Computing Practices and Letters
• /
• v.16 no.10
• /
• pp.975-979
• /
• 2010

Existing quality adaptation schemes are useful for improving network stability in a congested network, but these schemes do not guarantee the quality of experience on video streaming due to the frequent variations in playback quality for a streaming service. In this paper, we propose a network-adaptive quality adaptation scheme to guarantee the quality of experience on SVC(Scalable Video Coding) video streaming. The proposed scheme estimates the available bandwidth by bandwidth measurement scheme using media characteristic, and then smoothly adjusts the quality level of SVC video stream according to the estimated bandwidth. Through the simulation, we prove that our scheme guarantees the quality of experience for video streaming by minimizing quality variation.

• Journal of Digital Convergence
• /
• v.10 no.1
• /
• pp.21-28
• /
• 2012

E-participation is the term referring to the use of information and communication technologies to political participation by enabling citizens to connect with one another. Because e-participation systems are already constructed and operated, continuous usage is regarded as a major concern for successful e-participation. E-participation systems should guarantee ease of use, user satisfaction, and high quality. In addition, measuring the quality of e-participation systems will provide a useful strategy. This paper suggests a methodology for measuring quality of experience of the e-participation system and computing the quality score. We apply two concepts of usability measurement method and quality of experience that are most suitable. We provide the target of measurement,, the construct of quality of experience, the method of experiment and analysis of data, and the scoring method of quality of experience.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.8 no.12
• /
• pp.1811-1818
• /
• 2013

As the broadband network are being deployed recently, the IPTV (Internet Protocol TV) has appeared and become a most representative service that incorporates audio, video, etc. In spite of the long-period efforts, however, no standardized method exists to measure and evaluate the quality of video that is experienced through TV in the customer's premises. Therefore, before developing a method to measure and evaluate the quality of experience (QoE) for video that is the ultimate goal, this paper reviews the outcomes from the past standardization activities and drive a few important implications that would be reflected to the method to measure and evaluate QoE for video.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2015.10a
• /
• pp.1704-1706
• /
• 2015

디스플레이를 사용하는 스마트기기의 GUI는 품질 평가에 매우 중요한 요소이다. 그동안 GUI 품질 평가에 대한 연구는 사용성 평가와 같은 주관적 관점의 평가가 대부분 이었다. 이에 본 연구에서는 사용자가 직접적으로 체감할 수 있는 반응시간, 화면 움직임의 부드러움과 같은 항목으로 GUI의 체감품질을 정량화 할 수 있는 평가 모델을 제시하고자 한다.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.13 no.2
• /
• pp.427-434
• /
• 2018

Video services have been widely generalized thanks to the progress in compression streaming technologies. In spite of the innate difficulties in guaranteeing quality of service(QoS) of the Internet, the quality of service that is experienced by users have been improved considerably with overall bandwidth growth over the Internet and new compression and streaming technologies. For further sophisticated management scheme from the current homogeneous one, it should consider the characteristics of video contents. This paper investigates that the Quality of Experience(: QoE) for video services can vary according to the characteristics of video contents for the same compression method and transmission environments. It is expected that this result contributes to establish a new and advanced scheme to manage QoE for video services over the Internet.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.9 no.4
• /
• pp.491-498
• /
• 2014

As internet services are being provided through a wireless access, the importance of quality of experience (QoE) is stressed that is defined as the quality that indicates user's actual feeling when a service is provided. Unlike quality of service (QoS) that can be expressed as a numerical value, it is difficult to represent QoE in an objective way. If an internet service is serviced over a wireless channel, its QoE can be affected by a number of factors such as fading, mobility and so on. This paper, therefore, attempts to specify the relationship between QoE and QoS by conducting practical measurements for the voice service through 3G high speed packet access (HSPA) access network. Analysing the measured results, it has been shown that received signal strength indicator (RSSI) has a great influence on mean opinion score (MOS) through transmission delay.

• Proceedings of the Korean Information Science Society Conference
• /
• 2011.06d
• /
• pp.234-237
• /
• 2011

최근 인터넷을 통한 멀티미디어 스트리밍 서비스 이용이 증가함에 따라 스트리밍 서비스 품질을 향상 시키기 위한 연구들이 진행되고 있다. 하지만 기존 연구들은 네트워크 상태에 적응적으로 전송률을 조절함으로써 네트워크의 효율성 및 안전성을 개선하는데 초점을 맞추고 있어서 사용자 측면의 체감품질에 대한 고려가 부족하다. 본 논문에서는 멀티미디어 스트리밍 서비스의 사용자 체감품질 (QoE)을 향상시키기 위한 적응적인 전송률 및 비디오 품질 조절 기법을 제안한다. 제안하는 기법은 네트워크의 가용대역폭과 클라이언트의 버퍼 상태를 기반으로 전송률 및 비디오 품질을 조절함으로써 멀티미디어 재생의 불연속성과 잦은 비디오 품질 변화에 의한 사용자 체감품질을 개선하였다. 시험 결과를 통해서 제안하는 기법이 부드럽게 (Smoothly) 비디오 품질을 조절하는 것을 보였다.